Holier Than Thou - Biblical Contradictions

Was there really only one common language over the whole earth before the Tower of Babel?

Genesis 10:5, 20, 31, "(From these the maritime peoples spread out into their territories by their clans within their nations, each with its own language.) ...These are the sons of Ham by their clans and languages, in their territories and nations... These are the sons of Shem by their clans and languages, in their territories and nations."

Genesis 11:1, "Now the whole world had one language and a common speech."

Genesis 11:6-9, "The LORD said, 'If as one people speaking the same language they have begun to do this, then nothing they plan to do will be impossible for them. Come, let us go down and confuse their language so they will not understand each other.' So the LORD scattered them from there over all the earth, and they stopped building the city. That is why it was called Babel -- because there the LORD confused the language of the whole world. From there the LORD scattered them over the face of the whole earth."

According to Genesis chapter 11, the whole world had one common language, which was confounded by God during the construction of the tower of Babel, however, according to the previous chapter, each clan had its own language.

"Sorrow is better than laughter: for by the sadness of the countenance the heart is made better. The heart of the wise is in the house of mourning; but the heart of fools is in the house of mirth." (Ecclesiastes 7:3-4, KJV)

"Then I commended mirth, because a man hath no better thing under the sun, than to eat, and to drink, and to be merry: for that shall abide with him of his labour the days of his life, which God giveth him under the sun." (Ecclesiastes 8:15, KJV)